Final answer:
The most persuasive evidence for humans being one cause of the Pleistocene mass extinctions is the correlation between the timing of extinctions and human arrival in different regions. The disappearance of species in Australia and North America coincided with human arrival, as well as extinctions on remote oceanic islands. This evidence suggests that human hunting played a role in the extinctions.
Step-by-step explanation:
The most persuasive line of evidence that humans were one cause, even if not the only factor, in the Pleistocene mass extinctions is the correlation between the timing of the extinctions and the arrival of humans in different regions. In Australia, the extinctions began just after the arrival of humans, resulting in the disappearance of species such as the marsupial lion and giant kangaroo. The extinctions of large mammals in North America also coincided with human arrival in the area.
Furthermore, on remote oceanic islands, extinctions occurred coincidentally with human arrivals, forcing many species into extinction. Madagascar, which was colonized about 2,000 years ago, experienced the extinction of large mammals that lived there. This pattern suggests that human hunting precipitated the extinctions, even if climate change also played a role.
Overall, the relationship between the timing of the extinctions and the arrival of humans provides strong evidence that humans were one of the causes of the Pleistocene mass extinctions.